Error opening dwg files

So far I could open only a few drawings, quite small and simple ones. It failed to open all the larger ones. All of them were made using AutoCAD 2007/2008/2009. First I thought maybe the problem is that they contain 3D models, but I tried a lot which surely don't and it didn't work.

It either gives a message that DoubleCAD failed to open the drawing or it brakes like this: "DoubleCAD(tm) for Windows Application has encountered a problem and needs to close. We are sorry for the inconvenience.". Pffff

I just activated it, thinking maybe that'll help, but no.
I'm using Win XP prof x64... is that possibly the problem?

Would it be possible for you to let us see any of the files to get a feel for what is causing you problems? Any files that don't open that we can put in the hands of our development team can help them resolve the problems. If you can't share any of them (even privately rather than on the forum) can you describe them to us -- what application created them and was the last to save them in .dwg format; are they solid models, surface models, 2D plans; are they all > xxx number of layers or use special plugins... ? Any of that information could really help us.

Or try:DWG Repair Kit
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